4. _Coin and Medal Gallery_, fifty-six feet by seventeen.—As the dome of the Rotunda would only rise a few feet above the floor of this gallery, and would, from its curvature, recede to a distance of several feet, windows on the east side would be quite unobstructed. In each might stand a table-case, six or seven feet long, on which would be exhibited, under glass, a series of coins and medals which, though not the most valuable of our collection in the eyes of a numismatist, would suffice to give the public an interesting and instructive view of the monetary art. In the drawers of these cases might be kept the moulds and casts of the Coin Collection. Against the side walls might be upright cases, or frames, for extending the exhibition; but the walls facing the windows, having a front light, would be unsuitable for coins or medals, and must be employed for some other purpose. [Sidenote: PRIVATE ROOMS OF COIN DEPARTMENT.] 5. The rooms which remain would be a private suite for the Coin Department. The present rooms of that department are arranged in an order the reverse of what is best for security and convenience, the coins being kept in an outer room, which must be passed in going either to the Keeper’s study, or to the Ornament Room, a room open to all persons merely on application. In the accompanying plan the contents of the Ornament Room have been transferred to the Gem Room; and the Keeper’s study is placed near the beginning of the private suite. [Sidenote: OUTER COIN ROOM.] _Outer Coin Room_, twenty-eight feet by twenty-seven, for the freer exhibition of coins to properly introduced persons, for the use of artists copying coins or other minute objects, and all other purposes now served by the Medal Room, except the custody of the collection, and work of the department. [Sidenote: INNER COIN ROOM.] _Inner Coin Room_, fifty-five feet by twenty-eight, secured by a strong iron door, of which the Keeper, Assistant-Keeper, and Principal-Librarian, would alone have keys.—In this room, to which none but the departmental staff would be admitted, the coins and medals would be preserved, arranged, and catalogued; they would be carried hence by the officers into the Outer Room when required for inspection. The room is somewhat more than half as large again as the present Medal Room; and as the absence of visitors, and of the barriers their presence now requires, would leave the whole space free, there would be ample accommodation for any probable enlargement of the collection. The library of the department might be arranged partly in this, partly in the Outer Room.